T4 not talking to ECU

jki · 4th August 2008, 10:02

I wonder if any one can please.
I have an ABS warning light come on just before my MOT. Took it to local garage who put the T4 on but could not speak the ECU. Does anybody have any ideas ? I have had a fair amount of water in the plenum which is now cleared, and the ABS light was flickering for a while before coming on all the time. Please Help. Car ZT-T 190 +
thanks JKI

Mac_rouser · 4th August 2008, 10:08

hi jki
is the t4 a genuine rover t4 or is it a clone, for example a snap on diagnostics tool, some of these just simply wont talk to some 75's generally they will but there is always the odd one, so possibly it's off to an ex-rover dealer

Moonstone · 4th August 2008, 10:24

A commonly-reported problem is loose sensor wires rubbing against wheels, leading to failure. Check wheel arches.

Sensor faults are also possible. Without a diagnostic, it should be possible for a mechanic to do a resistance check. If your speedometer is still working, then the right-side front sensor is probably OK.

The diagnostic socket power fuse can sometimes be blown. It shares this fuse with the dash clock. Check for power on pin 16 (ground on 4 or 5).

jki · 4th August 2008, 11:44

Hi guys thanks for the posts.
Just a mobile auto elec guy, who plugged in his updated software and diagnosed a left rear speed sensor malfunction. Cost £25 but well worth it. Anybody know where I can get a sensor from. and is it easy to fit ?

Wolds_lady_2006 · 4th August 2008, 13:54

Dont want to alarm you BUT dont take what the diagnostics say, as the ultimate fault.

I too have this fault.

T4 highlighted the sensor, it was replaced, same fault shows up *-(
Tried another new sensor, as soon as it was fitted, T4 is reset and fault re occurs...

Hopefully you wont have this scenario....but be aware!

Good Luck

comet · 4th August 2008, 14:01

Buy a front sensor part Number SSB000150 and as your car will fail a MOT with the front offside one inop, it will be available for you to slave in at the conex's front AND rear.
Remember that the car with ignition to on, it will perform a integrity check of the sensors. If the light remains on go round the sensors front nearside and both back ones ,assuming that the speedo works OK. With ignition on you will eliminate the duff one.

If you put your area of residence in your profile and you live near me I could let you have mine to slave in.

jki · 8th August 2008, 13:53

Hi guys
thanks for the info. It was the left rear sensor, which I had changed all in for £75. Now everything ok. Many thanks

Keith · 9th August 2008, 12:24

T4 will indentify a failed ABS sensor for two reasons

Faulty sensor and or faulty wiring
Always check the wiring is ok before changing a sensor

OP T4 can sometimes have trouble talikng to some ECUS the system is pretty crude and over 10 years old!

I occasionally have problems taliking to Autoboxes with my T4 and I can gurantee trying to diagnose the Webasto FBH will cause most T4s to crash as the firmware in the FBH is not T4 friendly.

Often checking the obd connections are ok or a battery off reset or ensuring the car is on a charger ensures it talks eventually.

The V8 seems very prone to T4 comms problems based on comments made elsewhere but I have only had problems to date with one V8 though.

4th August 2008, 10:02	#1
jki Newbie MG ZT-T 190 + Join Date: Aug 2008 Location: Llannon Carmarthenshire Posts: 3 Thanks: 0 Thanked 0 Times in 0 Posts	T4 not talking to ECU I wonder if any one can please. I have an ABS warning light come on just before my MOT. Took it to local garage who put the T4 on but could not speak the ECU. Does anybody have any ideas ? I have had a fair amount of water in the plenum which is now cleared, and the ABS light was flickering for a while before coming on all the time. Please Help. Car ZT-T 190 + thanks JKI

4th August 2008, 10:08	#2
Mac_rouser Loves to post Rover 75 Saloon and 75 Tourer Join Date: Apr 2008 Location: Leeds Posts: 285 Thanks: 145 Thanked 69 Times in 34 Posts	hi jki is the t4 a genuine rover t4 or is it a clone, for example a snap on diagnostics tool, some of these just simply wont talk to some 75's generally they will but there is always the odd one, so possibly it's off to an ex-rover dealer __________________ Take care mac Rover 75 a classic

4th August 2008, 11:44	#4
jki Newbie MG ZT-T 190 + Join Date: Aug 2008 Location: Llannon Carmarthenshire Posts: 3 Thanks: 0 Thanked 0 Times in 0 Posts	T4 failure commincate Hi guys thanks for the posts. Just a mobile auto elec guy, who plugged in his updated software and diagnosed a left rear speed sensor malfunction. Cost £25 but well worth it. Anybody know where I can get a sensor from. and is it easy to fit ?

4th August 2008, 14:01	#6
comet Avid contributor CDTConnSE Wreg 102000mls Join Date: Nov 2006 Location: Grappenhall. Cheshire Posts: 105 Thanks: 3 Thanked 15 Times in 1 Post	Buy a front sensor part Number SSB000150 and as your car will fail a MOT with the front offside one inop, it will be available for you to slave in at the conex's front AND rear. Remember that the car with ignition to on, it will perform a integrity check of the sensors. If the light remains on go round the sensors front nearside and both back ones ,assuming that the speedo works OK. With ignition on you will eliminate the duff one. If you put your area of residence in your profile and you live near me I could let you have mine to slave in. Last edited by comet; 4th August 2008 at 14:04..

4th August 2008, 10:24	#3
Moonstone Loves to post Rover 75 Tourer Join Date: Nov 2006 Location: Scotland Posts: 412 Thanks: 0 Thanked 1 Time in 1 Post	A commonly-reported problem is loose sensor wires rubbing against wheels, leading to failure. Check wheel arches. Sensor faults are also possible. Without a diagnostic, it should be possible for a mechanic to do a resistance check. If your speedometer is still working, then the right-side front sensor is probably OK. The diagnostic socket power fuse can sometimes be blown. It shares this fuse with the dash clock. Check for power on pin 16 (ground on 4 or 5).

4th August 2008, 13:54	#5
Wolds_lady_2006 Loves to post MG ZT Join Date: Dec 2006 Location: North Lincolnshire Posts: 271 Thanks: 73 Thanked 28 Times in 23 Posts	Dont want to alarm you BUT dont take what the diagnostics say, as the ultimate fault. I too have this fault. T4 highlighted the sensor, it was replaced, same fault shows up *-( Tried another new sensor, as soon as it was fitted, T4 is reset and fault re occurs... Hopefully you wont have this scenario....but be aware! Good Luck

8th August 2008, 13:53	#7
jki Newbie MG ZT-T 190 + Join Date: Aug 2008 Location: Llannon Carmarthenshire Posts: 3 Thanks: 0 Thanked 0 Times in 0 Posts	Hi guys thanks for the info. It was the left rear sensor, which I had changed all in for £75. Now everything ok. Many thanks

9th August 2008, 12:24	#8
Keith This is my second home ZT400 Join Date: Oct 2006 Location: Ellesmere Posts: 5,948 Thanks: 0 Thanked 43 Times in 29 Posts	T4 will indentify a failed ABS sensor for two reasons Faulty sensor and or faulty wiring Always check the wiring is ok before changing a sensor OP T4 can sometimes have trouble talikng to some ECUS the system is pretty crude and over 10 years old! I occasionally have problems taliking to Autoboxes with my T4 and I can gurantee trying to diagnose the Webasto FBH will cause most T4s to crash as the firmware in the FBH is not T4 friendly. Often checking the obd connections are ok or a battery off reset or ensuring the car is on a charger ensures it talks eventually. The V8 seems very prone to T4 comms problems based on comments made elsewhere but I have only had problems to date with one V8 though.